Radiation damage in the bulk and at the surface.

The UK environmental e-science initiative supports the development and modification of simulation tools used to study\ud radiation damage effects. We discuss the development and modification to the DL_POLY molecular dynamics (MD) code.\ud Using the newly developed tools, we study the effects of radiation damage related to the safe encapsulation of highly\ud radioactive materials, including nuclear waste. We address the possible differences between the radiation damage in the bulk\ud and at the surface of a material, and perform MD simulations of energetic events in zircon structure.We find that in the case of\ud readily amorphizable material, the formation of a stable alternative covalent network reduces the possible effect of the surface\ud on the damaged structure